HOLCF: A higher-order version of LCF based on Isabelle/HOL

HOLCF is the definitional extension of Church's Higher-Order Logic with
Scott's Logic for Computable Functions that has been implemented in the
theorem prover Isabelle. This results in a flexible setup for reasoning
about functional programs. HOLCF supports standard domain theory (in particular
fixpoint reasoning and recursive domain equations) but also coinductive
arguments about lazy datatypes.